Reallocating resource capacity among resource pools in a cloud computing environment

ABSTRACT

In general, the embodiments of the present invention provide an approach for rebalancing/reallocating cloud resource capacities between resource pools that provide variable customer assurances and delivery penalties when assurances are not met. The variables that are considered hereunder include, overall ‘reservations’, total current capacity, remaining capacity against unused reservations and penalties that apply for failing to satisfy ‘reservation’ commitments. The approach uses a rate of capacity consumption to calculate the risk of consuming the available capacity in each resource pool (e.g., resource pools allocated to satisfy different levels of service with different SLA failure penalties). Based on the relative available capacity in each pool (as determined by the pool rate of consumption), resources are reallocated to maximize revenue (e.g., reduce financial penalty) across a resource pool set.

CROSS-REFERENCE TO RELATED APPLICATION

The present patent document is a continuation of U.S. patent applicationSer. No. 12/906,392, filed Oct. 18, 2010, entitled “REALLOCATINGRESOURCE CAPACITY AMONG RESOURCE POOLS IN A CLOUD COMPUTINGENVIRONMENT”, the disclosure of which is incorporated herein byreference.

TECHNICAL FIELD

The present invention generally relates to resource capacity allocation.Specifically, the present invention relates to the reallocation ofresource capacity among resource pools in a cloud computing environment.

BACKGROUND

The cloud computing environment is an enhancement to the predecessorgrid environment, whereby multiple grids and other computation resourcesmay be further abstracted by a cloud layer, thus making disparatedevices appear to an end-user as a single pool of seamless resources.These resources may include such things as physical or logical computeengines, servers and devices, device memory, storage devices, etc.

Consumers of cloud computing resources have differing needs andexpectations regarding the availability of computer resources. In somecases, the consumer's expectation is a best effort attempt that providesan inexpensive option to enhance total capacity to cover peaks or othersituations. In some cases a lack of extra capacity will not be highlydisruptive, it may be less optimal. In other cases, though the consumeris using cloud resources for handling peak demand or criticalrequirements, there is a fundamental expectation and need to be able torely on that capacity when it is needed (as if a flexible use‘reservation’ is in place). In the latter case, the consumer usuallyopts to pay additional fees to assure capacity on-demand to avoiddisruptive consequences (or, in other cases, to take advantage ofrelated pricing discounts due to the up-front financial commitment).Providing capacity assurance to a consumer creates a capacity planningchallenge for the cloud computing provider. The upfront fee is generallynot designed to cover the cost of reserving hardware for the consumersince that would not be economical for the consumer. Therefore, thecloud provider needs to allow that capacity to be used elsewhere, whilemaintaining a reasonable ability to satisfy the outstanding‘reservations’.

SUMMARY

In general, the embodiments of the present invention provide an approachfor rebalancing/reallocating cloud resource capacities between resourcepools that provide variable customer assurances and delivery penaltieswhen assurances are not met. The variables that are considered hereunderinclude, overall ‘reservations’, total current capacity, remainingcapacity against unused reservations and penalties that apply forfailing to satisfy ‘reservation’ commitments. The approach uses a rateof capacity consumption to calculate the risk of consuming the availablecapacity in each resource pool (e.g., resource pools allocated tosatisfy different levels of service with different Service LevelAgreement (SLA) failure penalties). Based on the relative availablecapacity in each pool (as determined by the pool rate of consumption),resources are reallocated to maximize revenue (e.g., reduce financialpenalty) across a resource pool set.

A first aspect of the present invention provides a method forreallocating resource capacity among resource pools in a cloud computingenvironment, comprising: receiving a request; classifying the requestbased on details of the request and an applicable set of Service LevelAgreement (SLA) terms; determining a rate of consumption and asaturation point of a set of resource pools based on fulfillment of therequest; determining a potential penalty for failing to fulfill futurerequests, the future requests being predicted based on the rate ofconsumption; and reallocating a resource capacity among the set ofresource pools based on the rate of consumption, the saturation point,and the potential penalty so that the potential penalty is minimized.

A second aspect of the present invention provides a system forreallocating resource capacity among resource pools in a cloud computingenvironment, comprising: a bus; a processor coupled to the bus; and amemory medium coupled to the bus, the memory medium comprisinginstructions to: receive a request; classify the request based ondetails of the request and an applicable set of Service Level Agreement(SLA) terms; determine a rate of consumption and a saturation point of aset of resource pools based on fulfillment of the request; determine apotential penalty for failing to fulfill future requests, the futurerequests being predicted based on the rate of consumption; andreallocate a resource capacity among the set of resource pools based onthe rate of consumption, the saturation point, and the potential penaltyso that the potential penalty is minimized.

A third aspect of the present invention provides a computer programproduct for reallocating resource capacity among resource pools in acloud computing environment, the computer program product comprising acomputer readable storage media, and program instructions stored on thecomputer readable storage media, to: receive a request; classify therequest based on details of the request and an applicable set of ServiceLevel Agreement (SLA) terms; determine a rate of consumption and asaturation point of a set of resource pools based on fulfillment of therequest; determine a potential penalty for failing to fulfill futurerequests, the future requests being predicted based on the rate ofconsumption; and reallocate a resource capacity among the set ofresource pools based on the rate of consumption, the saturation point,and the potential penalty so that the potential penalty is minimized.

A fourth aspect of the present invention provides a method for deployinga system for reallocating resource capacity among resource pools in acloud computing environment, comprising: deploying a computerinfrastructure being operable to: receive a request; classify therequest based on details of the request and an applicable set of ServiceLevel Agreement (SLA) terms; determine a rate of consumption and asaturation point of a set of resource pools based on fulfillment of therequest; determine a potential penalty for failing to fulfill futurerequests, the future requests being predicted based on the rate ofconsumption; and reallocate a resource capacity among the set ofresource pools based on the rate of consumption, the saturation point,and the potential penalty so that the potential penalty is minimized.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of this invention will be more readilyunderstood from the following detailed description of the variousaspects of the invention taken in conjunction with the accompanyingdrawings in which:

FIG. 1 depicts a cloud computing node according to an embodiment of thepresent invention.

FIG. 2 depicts a cloud computing environment according to an embodimentof the present invention.

FIG. 3 depicts abstraction model layers according to an embodiment ofthe present invention.

FIG. 4 depicts a first component flow diagram according to an embodimentof the present invention.

FIG. 5 depicts a second component flow diagram according to anembodiment of the present invention.

FIG. 6 depicts a method flow diagram according to an embodiment of thepresent invention.

The drawings are not necessarily to scale. The drawings are merelyschematic representations, not intended to portray specific parametersof the invention. The drawings are intended to depict only typicalembodiments of the invention, and therefore should not be considered aslimiting the scope of the invention. In the drawings, like numberingrepresents like elements.

DETAILED DESCRIPTION

Illustrative embodiments now will be described more fully herein withreference to the accompanying drawings, in which exemplary embodimentsare shown. This disclosure may, however, be embodied in many differentforms and should not be construed as limited to the exemplaryembodiments set forth herein. Rather, these exemplary embodiments areprovided so that this disclosure will be thorough and complete and willfully convey the scope of this disclosure to those skilled in the art.In the description, details of well-known features and techniques may beomitted to avoid unnecessarily obscuring the presented embodiments.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of this disclosure.As used herein, the singular forms “a”, “an”, and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. Furthermore, the use of the terms “a”, “an”, etc., do notdenote a limitation of quantity, but rather denote the presence of atleast one of the referenced items. It will be further understood thatthe terms “comprises” and/or “comprising”, or “includes” and/or“including”, when used in this specification, specify the presence ofstated features, regions, integers, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, regions, integers, steps, operations, elements,components, and/or groups thereof.

In general, the embodiments of the present invention provide an approachfor rebalancing/reallocating cloud resource capacities between resourcepools that provide variable customer assurances and delivery penaltieswhen assurances are not met. Additionally, the rate of consumptionallows the embodiments to forecast the likelihood of exhausting a givenpool in a specific period of time. The consumption rate calculationenables not just determining that resources are not only being exhaustedin a given pool, but when the resources will be depleted. This allowsthe forecasting of when a pool should grow in capacity. In any event,variables that are considered hereunder include, overall ‘reservations’,total current capacity, remaining capacity against unused reservations,and penalties that apply for failing to satisfy ‘reservation’commitments. The approach uses a rate of capacity consumption tocalculate the risk of consuming the available capacity in each resourcepool (e.g., resource pools allocated to satisfy different levels ofservice with different Service Level Agreement (SLA) failure penalties).Based on the relative available capacity in each pool (as determined bythe pool rate of consumption), resources are reallocated to maximizerevenue (e.g., reduce financial penalty) across a resource pool set.

It is understood in advance that although this disclosure includes adetailed description of cloud computing, implementation of the teachingsrecited herein are not limited to a cloud computing environment. Rather,embodiments of the present invention are capable of being implemented inconjunction with any other type of computing environment now known orlater developed.

Cloud computing is a model of service delivery for enabling convenient,on-demand network access to a shared pool of configurable computingresources (e.g. networks, network bandwidth, servers, processing,memory, storage, applications, virtual machines, and services) that canbe rapidly provisioned and released with minimal management effort orinteraction with a provider of the service. This cloud model may includeat least five characteristics, at least three service models, and atleast four deployment models.

Characteristics are as follows:

On-demand self-service: a cloud consumer can unilaterally provisioncomputing capabilities, such as server time and network storage, asneeded, automatically without requiring human interaction with theservice's provider.

Broad network access: capabilities are available over a network andaccessed through standard mechanisms that promote use by heterogeneousthin or thick client platforms (e.g., mobile phones, laptops, and PDAs).

Resource pooling: the provider's computing resources are pooled to servemultiple consumers using a multi-tenant model, with different physicaland virtual resources dynamically assigned and reassigned according todemand. There is a sense of location independence in that the consumergenerally has no control or knowledge over the exact location of theprovided resources but may be able to specify location at a higher levelof abstraction (e.g., country, state, or datacenter).

Rapid elasticity: capabilities can be rapidly and elasticallyprovisioned, in some cases automatically, to quickly scale out andrapidly released to quickly scale in. To the consumer, the capabilitiesavailable for provisioning often appear to be unlimited and can bepurchased in any quantity at any time.

Measured service: cloud systems automatically control and optimizeresource use by leveraging a metering capability at some level ofabstraction appropriate to the type of service (e.g., storage,processing, bandwidth, and active user accounts). Resource usage can bemonitored, controlled, and reported providing transparency for both theprovider and consumer of the utilized service.

Service Models are as follows:

Software as a Service (SaaS): the capability provided to the consumer isto use the provider's applications running on a cloud infrastructure.The applications are accessible from various client devices through athin client interface such as a web browser (e.g., web-based email). Theconsumer does not manage or control the underlying cloud infrastructureincluding network, servers, operating systems, storage, or evenindividual application capabilities, with the possible exception oflimited user-specific application configuration settings.

Platform as a Service (PaaS): the capability provided to the consumer isto deploy onto the cloud infrastructure consumer-created or acquiredapplications created using programming languages and tools supported bythe provider. The consumer does not manage or control the underlyingcloud infrastructure including networks, servers, operating systems, orstorage, but has control over the deployed applications and possiblyapplication-hosting environment configurations.

Infrastructure as a Service (IaaS): the capability provided to theconsumer is to provision processing, storage, networks, and otherfundamental computing resources where the consumer is able to deploy andrun arbitrary software, which can include operating systems andapplications. The consumer does not manage or control the underlyingcloud infrastructure but has control over operating systems, storage,deployed applications, and possibly limited control of select networkingcomponents (e.g., host firewalls).

Deployment Models are as follows:

Private cloud: the cloud infrastructure is operated solely for anorganization. It may be managed by the organization or a third party andmay exist on-premises or off-premises.

Community cloud: the cloud infrastructure is shared by severalorganizations and supports a specific community that has shared concerns(e.g., mission, security requirements, policy, and complianceconsiderations). It may be managed by the organizations or a third partyand may exist on-premises or off-premises.

Public cloud: the cloud infrastructure is made available to the generalpublic or a large industry group and is owned by an organization sellingcloud services.

Hybrid cloud: the cloud infrastructure is a composition of two or moreclouds (private, community, or public) that remain unique entities butare bound together by standardized or proprietary technology thatenables data and application portability (e.g., cloud bursting forload-balancing between clouds).

A cloud computing environment is service oriented with a focus onstatelessness, low coupling, modularity, and semantic interoperability.At the heart of cloud computing is an infrastructure comprising anetwork of interconnected nodes.

Referring now to FIG. 1, a schematic of an example of a cloud computingnode is shown. Cloud computing node 10 is only one example of a suitablecloud computing node and is not intended to suggest any limitation as tothe scope of use or functionality of embodiments of the inventiondescribed herein. Regardless, cloud computing node 10 is capable ofbeing implemented and/or performing any of the functionality set forthhereinabove.

In cloud computing node 10, there is a computer system/server 12, whichis operational with numerous other general purpose or special purposecomputing system environments or configurations. Examples of well-knowncomputing systems, environments, and/or configurations that may besuitable for use with computer system/server 12 include, but are notlimited to, personal computer systems, server computer systems, thinclients, thick clients, hand-held or laptop devices, multiprocessorsystems, microprocessor-based systems, set top boxes, programmableconsumer electronics, network PCs, minicomputer systems, mainframecomputer systems, and distributed cloud computing environments thatinclude any of the above systems or devices, and the like.

Computer system/server 12 may be described in the general context ofcomputer system-executable instructions, such as program modules, beingexecuted by a computer system. Generally, program modules may includeroutines, programs, objects, components, logic, data structures, and soon that perform particular tasks or implement particular abstract datatypes. Computer system/server 12 may be practiced in distributed cloudcomputing environments where tasks are performed by remote processingdevices that are linked through a communications network. In adistributed cloud computing environment, program modules may be locatedin both local and remote computer system storage media including memorystorage devices.

As shown in FIG. 1, computer system/server 12 in cloud computing node 10is shown in the form of a general-purpose computing device. Thecomponents of computer system/server 12 may include, but are not limitedto, one or more processors or processing units 16, a system memory 28,and a bus 18 that couples various system components including systemmemory 28 to processor 16.

Bus 18 represents one or more of any of several types of bus structures,including a memory bus or memory controller, a peripheral bus, anaccelerated graphics port, and a processor or local bus using any of avariety of bus architectures. By way of example, and not limitation,such architectures include Industry Standard Architecture (ISA) bus,Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA) bus, VideoElectronics Standards Association (VESA) local bus, and PeripheralComponent Interconnects (PCI) bus.

Computer system/server 12 typically includes a variety of computersystem readable media. Such media may be any available media that isaccessible by computer system/server 12, and it includes both volatileand non-volatile media, removable and non-removable media.

System memory 28 can include computer system readable media in the formof volatile memory, such as random access memory (RAM) 30 and/or cachememory 32. Computer system/server 12 may further include otherremovable/non-removable, volatile/non-volatile computer system storagemedia. By way of example only, storage system 34 can be provided forreading from and writing to a non-removable, non-volatile magnetic media(not shown and typically called a “hard drive”). Although not shown, amagnetic disk drive for reading from and writing to a removable,non-volatile magnetic disk (e.g., a “floppy disk”), and an optical diskdrive for reading from or writing to a removable, non-volatile opticaldisk such as a CD-ROM, DVD-ROM, or other optical media can be provided.In such instances, each can be connected to bus 18 by one or more datamedia interfaces. As will be further depicted and described below,memory 28 may include at least one program product having a set (e.g.,at least one) of program modules that are configured to carry out thefunctions of embodiments of the invention.

The embodiments of the invention may be implemented as a computerreadable signal medium, which may include a propagated data signal withcomputer readable program code embodied therein (e.g., in baseband or aspart of a carrier wave). Such a propagated signal may take any of avariety of forms including, but not limited to, electro-magnetic,optical, or any suitable combination thereof. A computer readable signalmedium may be any computer readable medium that is not a computerreadable storage medium and that can communicate, propagate, ortransport a program for use by or in connection with an instructionexecution system, apparatus, or device.

Program code embodied on a computer readable medium may be transmittedusing any appropriate medium including, but not limited to, wireless,wireline, optical fiber cable, radio-frequency (RF), etc., or anysuitable combination of the foregoing.

Program/utility 40, having a set (at least one) of program modules 42,may be stored in memory 28 by way of example, and not limitation, aswell as an operating system, one or more application programs, otherprogram modules, and program data. Each of the operating system, one ormore application programs, other program modules, and program data orsome combination thereof, may include an implementation of a networkingenvironment. Program modules 42 generally carry out the functions and/ormethodologies of embodiments of the invention as described herein.

Computer system/server 12 may also communicate with one or more externaldevices 14 such as a keyboard, a pointing device, a display 24, etc.;one or more devices that enable a user to interact with computersystem/server 12; and/or any devices (e.g., network card, modem, etc.)that enable computer system/server 12 to communicate with one or moreother computing devices. Such communication can occur via I/O interfaces22. Still yet, computer system/server 12 can communicate with one ormore networks such as a local area network (LAN), a general wide areanetwork (WAN), and/or a public network (e.g., the Internet) via networkadapter 20. As depicted, network adapter 20 communicates with the othercomponents of computer system/server 12 via bus 18. It should beunderstood that although not shown, other hardware and/or softwarecomponents could be used in conjunction with computer system/server 12.Examples include, but are not limited to: microcode, device drivers,redundant processing units, external disk drive arrays, RAID systems,tape drives, and data archival storage systems, etc.

Referring now to FIG. 2, illustrative cloud computing environment 50 isdepicted. As shown, cloud computing environment 50 comprises one or morecloud computing nodes 10 with which local computing devices used bycloud consumers, such as, for example, personal digital assistant (PDA)or cellular telephone 54A, desktop computer 54B, laptop computer 54C,and/or automobile computer system 54N may communicate. Nodes 10 maycommunicate with one another. They may be grouped (not shown) physicallyor virtually, in one or more networks, such as private, community,public, or hybrid clouds as described hereinabove, or a combinationthereof. This allows cloud computing environment 50 to offerinfrastructure, platforms, and/or software as services for which a cloudconsumer does not need to maintain resources on a local computingdevice. It is understood that the types of computing devices 54A-N shownin FIG. 2 are intended to be illustrative only and that computing nodes10 and cloud computing environment 50 can communicate with any type ofcomputerized device over any type of network and/or network addressableconnection (e.g., using a web browser).

Referring now to FIG. 3, a set of functional abstraction layers providedby cloud computing environment 50 (FIG. 2) is shown. It should beunderstood in advance that the components, layers, and functions shownin FIG. 3 are intended to be illustrative only and embodiments of theinvention are not limited thereto. As depicted, the following layers andcorresponding functions are provided:

Hardware and software layer 60 includes hardware and softwarecomponents. Examples of hardware components include mainframes. In oneexample, IBM® zSeries® systems and RISC (Reduced Instruction SetComputer) architecture based servers. In one example, IBM pSeries®systems, IBM xSeries® systems, IBM BladeCenter® systems, storagedevices, networks, and networking components. Examples of softwarecomponents include network application server software. In one example,IBM WebSphere® application server software and database software. In oneexample, IBM DB2® database software. (IBM, zSeries, pSeries, xSeries,BladeCenter, WebSphere, and DB2 are trademarks of International BusinessMachines Corporation registered in many jurisdictions worldwide.)

Virtualization layer 62 provides an abstraction layer from which thefollowing examples of virtual entities may be provided: virtual servers;virtual storage; virtual networks, including virtual private networks;virtual applications and operating systems; and virtual clients.

In one example, management layer 64 may provide the functions describedbelow. Resource provisioning provides dynamic procurement of computingresources and other resources that are utilized to perform tasks withinthe cloud computing environment. Metering and pricing provide costtracking as resources are utilized within the cloud computingenvironment, and billing or invoicing for consumption of theseresources. In one example, these resources may comprise applicationsoftware licenses. Security provides identity verification for cloudconsumers and tasks, as well as protection for data and other resources.User portal provides access to the cloud computing environment forconsumers and system administrators. Service level management providescloud computing resource allocation and management such that requiredservice levels are met. Service Level Agreement (SLA) planning andfulfillment provides pre-arrangement for, and procurement of, cloudcomputing resources for which a future requirement is anticipated inaccordance with an SLA.

Workloads layer 66 provides examples of functionality for which thecloud computing environment may be utilized. Examples of workloads andfunctions which may be provided from this layer include: mapping andnavigation; software development and lifecycle management; virtualclassroom education delivery; data analytics processing; transactionprocessing; and capacity reallocation. As mentioned above, all of theforegoing examples described with respect to FIG. 3 are illustrativeonly, and the invention is not limited to these examples.

It is understood all functions of the present invention as describedherein are typically performed by the capacity reallocation function,which can be tangibly embodied as modules of program code 42 ofprogram/utility 40 (FIG. 1). However, this need not be the case. Rather,the functionality recited herein could be carried out/implemented and/orenabled by any of the layers 60-66 shown in FIG. 3.

It is reiterated that although this disclosure includes a detaileddescription on cloud computing, implementation of the teachings recitedherein are not limited to a cloud computing environment. Rather, theembodiments of the present invention are intended to be implemented withany type of clustered computing environment now known or laterdeveloped.

In a traditional IT environment, the solution to providing a consumerwith an assurance of available computing capacity is to set asideresources that will be used to satisfy an incoming request. Though itprovides complete assurance that the capacity will be available whenneeded, it is neither scalable nor economically viable when a usagebased pricing model is coupled with the environment as in a cloudcomputer context. That is, unless the consumer uses the capacitycontinuously, the time the capacity is not in use is a continuing costto the cloud provider that has no revenue to cover time when thecapacity is idle.

A flexible cloud environment provides a mapping of cost to revenue, butdoes little to keep on-demand consumers (those having no ‘reservations’)from saturating the computing resources and leaving a lack of resourcesto enable the cloud provider to satisfy ‘reservations’. In this model,one of the only viable options to satisfy the ‘reservations’ in the caseof a saturated cloud is to begin shutting down the on-demand instances.Though that may be financially advantageous if there is little or nopenalty for those shutdowns, it is likely to quickly lead to instanceand reputation impacts that will greatly reduce the on-demand usage ofthe cloud and likely increase the ‘reservation’ problem due to the lackof on-demand use providing revenue coverage.

The approach outlined herein provides a hybrid approach that dynamicallybalances resources between pools of variable assurance or financialpenalty. In a typical embodiment, there are at least two resource pools.One pool has no penalty for not being able to provide resources whenrequested. The other pool has a financial penalty for any request thatcannot be satisfied. This model can easily be expanded to leverage a setof pools that each has differing penalty impact levels ranging fromno-penalty for lack of capacity to the maximum penalty for lack ofcapacity. In each cloud computing environment, the allocations and riskprofiles will be unique to the circumstances, but the following strategyprovides an approach to optimize the providers' ability to recoup costswhile still providing the opportunity for consumers to request‘reservations’.

One aspect of this approach is the management of risk. Risk cannot beeliminated unless a complete environment capable of satisfying anyoutstanding reservations with the available unallocated capacity isprovided. In order to provide cloud resources at a competitive price,the cloud provider needs to optimize by reducing this available capacityto an amount less than the outstanding reservations and thus introducerisk. The amount of capacity kept free for ‘reservation’ use is drivenby the relationship between the revenue for capacity and the penalty forfailing to satisfy a reservation. An added complexity is the fact thatthere will be potentially multiple ‘reservations’ with each having itsown penalty. These may need to be managed individually such that thenumber of reservations impacted (or the least financially relevant) isminimized.

Prior to any reservation requests, the cloud provider would allocate allresources to the on-demand pool to satisfy reservation-less requests. Asreservations are created, resources will be transferred into thereservation pool(s) as indicated by the provider risk profile.

Balancing the risk across the pools is based on several key metrics thatare defined here:

Rate of Instance De-provisioning=Number of, or overall capacity ofinstances that free up per unit of time, primarily oriented aroundpredicting the rate at which a cloud would become available without newinstances coming online.

Rate of Instance Provisioning=Number of, or overall capacity ofinstances that are consumed per unit of time, primarily oriented aroundpredicting the rate at which a cloud would become unavailable withoutinstances being de-provisioned.

Rate of Consumption=Net number of, or overall capacity of instances thatare consumed.

Reserved Capacity=Total number of, or overall capacity of instances thatare reserved in a given pool.

Reservation Capacity=Total number of, or overall capacity of instancesthat are available to satisfy the reservations in a given pool.

On-demand Capacity=Total number of, or overall capacity of instancesthat are available to satisfy the on-demand requests.

Algorithm: The following approach describes an algorithm for managingthe capacity to maintain a balance between the on-demand and reservationenvironments. Though the approach can be expanded to cascade acrossmultiple environments, it will demonstrate the approach with only twopools of capacity for illustrative purposes.

Pool A—On-demand pool. No penalty for lack of capacity.

Pool B—Reservation pool. Penalties apply for not providing expectedcapacity. In this case, the penalties are greater than the revenue thatis acquired by an on-demand reservation. In this model, the followingalgorithm may be used to manage the capacity between the two pools:

Steady State (No New Reservations Involved)

(1) Calculate the rate of consumption in Pool B;

(2) Determine the time until saturation;

(3) If the time is less than the risk threshold, initiate the transferof capacity from Pool A to Pool B

-   -   Calculate the transfer amount based on a target threshold that        is greater than the risk threshold to provide a pre-determined        buffer before the analysis is likely to require capacity        transfer again    -   If Pool A does not have adequate available capacity, initiate        partial transfer and discontinue on-demand provisioning until        sufficient capacity has been transferred;    -   Alerts need to be raised if the Rate of Instance De-provisioning        in Pool A is not high enough to achieve the capacity transfer        needed prior to Pool B saturating;    -   If Pool A does not have sufficient capacity overall, additional        alerts need to be raised to actually initiate an overall        capacity increase (though it is not likely that getting to this        point in the steady state algorithm will be a sufficiently        timely option); and

(4) If the time is greater than the overcapacity threshold,conditionally initiate the transfer of capacity from Pool B to Pool A;

-   -   Use the Rate of Consumption of Pool A to determine if it is on        pace to saturate within a window of time worth adding capacity        immediately (set based on cost of transferring capacity against        a business defined time window). It should be noted that        transferring capacity back to Pool A may only be practical if        the On-Demand use will use the capacity since it does not cost        more to be in one pool or the other. It should be noted that in        the case where there are more than two pools, the logic could        cascade from the most critical pool back through the        decreasingly critical pools to access additional storage.        Instead of just taking the least critical capacity (which would        consistently leave that pool starved), it would look for the        most extraneous capacity (that which has extended time until        saturation), taking from the least critical of those pools.

Referring now to FIG. 4, a component flow diagram according to anembodiment of the present invention is shown. As depicted, the processis as follows:

1—A user requests an instance and it is classified as against eithertheir reserved or unreserved capacity;

2—Based on a classification, the request is directed to either areservation pool or an unreserved pool;

3—The request is time stamped, and the rate engine determines theoverall frequency of provision and de-provision requests of eachcategory;

3b—Frequency of change in the environment is periodically sent to a coreanalytic engine 70 (which can comprise program/utility 40 having programmodules 42 of FIG. 1);

4—The instance is provisioned in the appropriate pool;

5—On a periodic basis, the total used and available capacity within thepool is analyzed;

6—Total used and available capacity is communicated to core analyticengine 70;

7—Based on current capacity in each pool and on the rate of consumptionof each pool, a cost/price analysis is performed, identifying the mostrevenue-optimal use of resources for the current infrastructure.User-selectable parameters could include the acceptable risk ofprovisioning failure, the frequency of analysis, cost of movingresources from one pool to another, and the duration of the forecast;

8—Core analytic engine 70 determines the rate of consumption andcompares it to the saturation/risk threshold. It initiates calls to thepool resizing engine to move resources from one pool to another, inaccordance with the most optimal configuration of settings;

9—Pool resizing executes changes to move resources from one pool toanother;

Referring now to FIG. 5, another component flow diagram according toanother embodiment of the present invention is shown. As depicted, theprocess is as follows:

1—A user requests an instance and it is classified as against eithertheir reserved or unreserved capacity;

2—The request is time-stamped, the overall frequency of provision andde-provision requests of each category are determined;

3—A frequency of change in the environment is periodically sent to theanalytics engine;

4—The request is sent to core analytic engine 70 to determine theappropriate location for resource (e.g., virtual machine) and theappropriate pool size;

5—Core analytic engine 70 consults the pool capacity component todetermine the most optimal location for this request (satisfying alluser requested conditions). It also interacts with the cost/priceanalysis engine to determine the most financially efficient way to bothsatisfy the request and to manage the remainder of the infrastructure.Core analytic engine 70 determines the rate of consumption and comparesit to the saturation/risk threshold. It initiates calls to the poolresizing engine to move resources from one pool to another, inaccordance with the most optimal configuration of settings;

6—Core analytic engine 70 sends commands to the pool resizing componentto adjust the size of the pools in accordance with core analytic engine70's output;

7—The user's resource (e.g., virtual machine) is requested against aspecific (optimal) system within the optimal pool;

8—The user's resource (e.g., virtual machine) is provisioned;

9—Pool resizing executes reallocation of resources from one pool toanother; and

10—The pool capacity component is updated with current capacity data

As can be seen, under these embodiments, virtual resources can besegmented flexibly out of physical resources. For example, a variablequantity of virtual machines can be created out of the same physicalserver. This plasticity in the resources makes this analytic engine verydynamic. Moreover, core analytic engine 70 can move things around tomake room for a new virtual machine, and core analytic engine 70 does sowhile considering the current pool size information, cost of moving,revenue potential, current pool sizes, cost of moving (at the time ofrequest). Still yet, real-time dynamic information provided hereunderabout available resources (pools), costs of resources, costs of movingvirtual resources, and projected provisioning and de-provisioningpatterns make the optimal answers given by core analytic engine 70different at different times. Further, in the interest of fastprovisioning, core analytic engine 70 can make the resource allocationdecision in parallel with a scheduled pool resize decision.

Referring now to FIG. 6, a method flow diagram in accordance with theseembodiments is shown. In step S1, a request is received. In step S2, therequest is classified based on details of the request and an applicableset of Service Level Agreement (SLA) terms. In step S3, a rate ofconsumption and a saturation point of a set of resource pools (e.g., anon-demand based resource pool, and a reservation based resource pool)are determined based on fulfilling the request. The saturation point canbe determined based on a provisioning rate and a de-provisioning rate ofthe set of resource pools. In step S4, a potential penalty (e.g.,financial penalty) for failing to fulfill future requests is determined.As mentioned above, the future requests are predicted based on the rateof consumption. In step S5, a resource capacity (e.g., a CentralProcessing Unit (CPU) capacity, a memory capacity, a storage capacity, avirtual machine capacity, or a network location) is reallocated amongthe set of resource pools based on the rate of consumption, thesaturation point, and the potential penalty, so that future requests canbe fulfilled and/or the potential penalty can be minimized.

As indicated above, the reallocation can occur from the on-demand basedresource pool to the reservation based resource pool so that thescheduled future jobs can be fulfilled and the potential penalty can beavoided. However, in another embodiment the set of resource pools cancomprise at least three resource pools. In such an embodiment, thereallocation can occur from a resource pool having a lower potentialpenalty to a resource pool having a higher potential penalty.

While shown and described herein as a resource capacity reallocationsolution, it is understood that the invention further provides variousalternative embodiments. For example, in one embodiment, the inventionprovides a computer-readable/useable medium that includes computerprogram code to enable a computer infrastructure to provide resourcecapacity reallocation functionality as discussed herein. To this extent,the computer-readable/useable medium includes program code thatimplements each of the various processes of the invention. It isunderstood that the terms computer-readable medium or computer-useablemedium comprise one or more of any type of physical embodiment of theprogram code. In particular, the computer-readable/useable medium cancomprise program code embodied on one or more portable storage articlesof manufacture (e.g., a compact disc, a magnetic disk, a tape, etc.), onone or more data storage portions of a computing device, such as memory28 (FIG. 1) and/or storage system 34 (FIG. 1) (e.g., a fixed disk, aread-only memory, a random access memory, a cache memory, etc.).

In another embodiment, the invention provides a method that performs theprocess of the invention on a subscription, advertising, and/or feebasis. That is, a service provider, such as a Solution Integrator, couldoffer to provide resource capacity reallocation functionality. In thiscase, the service provider can create, maintain, support, etc., acomputer infrastructure, such as computer system 12 (FIG. 1) thatperforms the processes of the invention for one or more consumers. Inreturn, the service provider can receive payment from the consumer(s)under a subscription and/or fee agreement and/or the service providercan receive payment from the sale of advertising content to one or morethird parties.

In still another embodiment, the invention provides acomputer-implemented method for resource capacity reallocation. In thiscase, a computer infrastructure, such as computer system 12 (FIG. 1),can be provided and one or more systems for performing the processes ofthe invention can be obtained (e.g., created, purchased, used, modified,etc.) and deployed to the computer infrastructure. To this extent, thedeployment of a system can comprise one or more of: (1) installingprogram code on a computing device, such as computer system 12 (FIG. 1),from a computer-readable medium; (2) adding one or more computingdevices to the computer infrastructure; and (3) incorporating and/ormodifying one or more existing systems of the computer infrastructure toenable the computer infrastructure to perform the processes of theinvention.

As used herein, it is understood that the terms “program code” and“computer program code” are synonymous and mean any expression, in anylanguage, code, or notation, of a set of instructions intended to causea computing device having an information processing capability toperform a particular function either directly or after either or both ofthe following: (a) conversion to another language, code, or notation;and/or (b) reproduction in a different material form. To this extent,program code can be embodied as one or more of: an application/softwareprogram, component software/a library of functions, an operating system,a basic device system/driver for a particular computing device, and thelike.

A data processing system suitable for storing and/or executing programcode can be provided hereunder and can include at least one processorcommunicatively coupled, directly or indirectly, to memory elementsthrough a system bus. The memory elements can include, but are notlimited to, local memory employed during actual execution of the programcode, bulk storage, and cache memories that provide temporary storage ofat least some program code in order to reduce the number of times codemust be retrieved from bulk storage during execution. Input/outputand/or other external devices (including, but not limited to, keyboards,displays, pointing devices, etc.) can be coupled to the system eitherdirectly or through intervening device controllers.

Network adapters also may be coupled to the system to enable the dataprocessing system to become coupled to other data processing systems,remote printers, storage devices, and/or the like, through anycombination of intervening private or public networks. Illustrativenetwork adapters include, but are not limited to, modems, cable modems,and Ethernet cards.

The foregoing description of various aspects of the invention has beenpresented for purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formdisclosed and, obviously, many modifications and variations arepossible. Such modifications and variations that may be apparent to aperson skilled in the art are intended to be included within the scopeof the invention as defined by the accompanying claims.

What is claimed is:
 1. A method for reallocating resource capacity amongresource pools in a cloud computing environment, comprising: receiving arequest for an instance of a virtual machine; classifying the requestbased on details of the request and an applicable set of Service LevelAgreement (SLA) terms; determining a rate of consumption and asaturation point of a set of resource pools based on fulfillment of therequest, the set of resource pools comprising a reservation based pooland an on-demand based pool; determining a potential penalty for failingto fulfill future requests for instances in the reservation based pool,the future requests being predicted based on the rate of consumption;calculating a risk of failure to the fulfill future requests among theset of resource pools based on at least one of a rate of instancede-provisioning, a rate of instance-provisioning, a rate of consumption,a reserved capacity, a reservation capacity, and an on-demand capacity;calculating an amount of resource capacity necessary for the reservationbased pool based on the risk, the rate of consumption, the saturationpoint, and the potential penalty so that the potential penalty isminimized; estimating an amount of resource capacity that willpotentially be consumed in the reservation based pool, in addition tothe calculated amount of resource capacity necessary for the reservationbased pool, between a time of a reallocation of the calculated amount ofresource capacity and a time of another reallocation; calculating anamount of a capacity required to be transferred from the on-demand basedpool to the reservation based pool to fulfill the calculated amount ofresource capacity and the estimated amount of resource capacity;initiating a transfer of resource capacity from the on-demand based poolto the reservation based pool; discontinuing on-demand provisioninguntil sufficient capacity has been transferred if the on-demand basedpool does not have adequate capacity to achieve the capacity transfer;and providing bandwidth in accordance with the distribution of theresource capacity among the on-demand based pool and the reservationbased pool.
 2. The method of claim 1, the resource capacity comprisingat least one of the following: a Central Processing Unit (CPU) capacity,a memory capacity, a storage capacity, a virtual machine capacity, or anetwork location.
 3. The method of claim 1, further comprising selectinga resource pool from the set of resource pools for fulfilling therequest.
 4. The method of claim 1, the potential penalty comprising afinancial penalty.
 5. The method of claim 1, further comprising:determining a provisioning rate and a de-provisioning rate of the set ofresource pools; and using the provisioning rate and the de-provisioningrate to determine the rate of consumption and the saturation point. 6.The method of claim 1, wherein a service solution provider provides acomputer infrastructure that performs the method for one or moreconsumers.
 7. The method of claim 1, the set of resource poolscomprising at least three resource pools.
 8. The method of claim 1, thereallocating being performed asynchronous with a processing of therequest.
 9. The method of claim 1, the reallocation occurring from theon-demand based resource pool to the reservation based resource pool sothe potential penalty can be minimized.
 10. A system for reallocatingresource capacity among resource pools in a cloud computing environment,comprising: a bus; a processor coupled to the bus; and a memory mediumcoupled to the bus, the memory medium comprising instructions to:receive a request for an instance of a virtual machine; classify therequest based on details of the request and an applicable set of ServiceLevel Agreement (SLA) terms; determine a rate of consumption and asaturation point of a set of resource pools based on fulfillment of therequest, the set of resource pools comprising a reservation based pooland an on-demand based pool; determine a potential penalty for failingto fulfill future requests for instances in the reservation based pool,the future requests being predicted based on the rate of consumption;calculate a risk of failure to the fulfill future requests among the setof resource pools based on at least one of a rate of instancede-provisioning, a rate of instance-provisioning, a rate of consumption,a reserved capacity, a reservation capacity, and an on-demand capacity;calculate an amount of resource capacity necessary for the reservationbased pool based on the risk, the rate of consumption, the saturationpoint, and the potential penalty so that the potential penalty isminimized; estimate an amount of resource capacity that will potentiallybe consumed in the reservation based pool, in addition to the calculatedamount of resource capacity necessary for the reservation based pool,between a time of a reallocation of the calculated amount of resourcecapacity and a time of another reallocation; calculate an amount of acapacity required to be transferred from the on-demand based pool to thereservation based pool to fulfill the calculated amount of resourcecapacity and the estimated amount of resource capacity; initiate atransfer of resource capacity from the on-demand based pool to thereservation based pool; discontinue on-demand provisioning untilsufficient capacity has been transferred if the on-demand based pooldoes not have adequate capacity to achieve the capacity transfer; andprovide bandwidth in accordance with the distribution of the resourcecapacity among the on-demand based pool and the reservation based pool.11. The system of claim 10, the resource capacity comprising at leastone of the following: a Central Processing Unit (CPU) capacity, a memorycapacity, a storage capacity, a virtual machine capacity, or a networklocation.
 12. The system of claim 10, the memory medium furthercomprising instructions to select a resource pool from the set ofresource pools for fulfilling the request.
 13. The system of claim 10,the potential penalty comprising a financial penalty.
 14. The system ofclaim 10, the memory medium further comprising instructions to:determine a provisioning rate and a de-provisioning rate of the set ofresource pools; and use the provisioning rate and the de-provisioningrate to determine the rate of consumption and the saturation point. 15.A computer program product for reallocating resource capacity amongresource pools in a cloud computing environment, the computer programproduct comprising a computer readable storage media, and programinstructions stored on the computer readable storage media, to: receivea request for an instance of a virtual machine; classify the requestbased on details of the request and an applicable set of Service LevelAgreement (SLA) terms; determine a rate of consumption and a saturationpoint of a set of resource pools based on fulfillment of the request,the set of resource pools comprising a reservation based pool and anon-demand based pool; determine a potential penalty for failing tofulfill future requests for instances in the reservation based pool, thefuture requests being predicted based on the rate of consumption;calculate a risk of failure to the fulfill future requests among the setof resource pools based on at least one of a rate of instancede-provisioning, a rate of instance-provisioning, a rate of consumption,a reserved capacity, a reservation capacity, and an on-demand capacity;calculate an amount of resource capacity necessary for the reservationbased pool based on the risk, the rate of consumption, the saturationpoint, and the potential penalty so that the potential penalty isminimized; estimate an amount of resource capacity that will potentiallybe consumed in the reservation based pool, in addition to the calculatedamount of resource capacity necessary for the reservation based pool,between a time of a reallocation of the calculated amount of resourcecapacity and a time of another reallocation; calculate an amount of acapacity required to be transferred from the on-demand based pool to thereservation based pool to fulfill the calculated amount of resourcecapacity and the estimated amount of resource capacity; initiate atransfer of resource capacity from the on-demand based pool to thereservation based pool; discontinue on-demand provisioning untilsufficient capacity has been transferred if the on-demand based pooldoes not have adequate capacity to achieve the capacity transfer; andprovide bandwidth in accordance with the distribution of the resourcecapacity among the on-demand based pool and the reservation based pool.16. The computer program product of claim 15, the resource capacitycomprising at least one of the following: a Central Processing Unit(CPU) capacity, a memory capacity, a storage capacity, a virtual machinecapacity, or a network location.
 17. The computer program product ofclaim 15, further comprising program instructions stored on the computerreadable storage media to select a resource pool from the set ofresource pools for fulfilling the request.
 18. The computer programproduct of claim 15, the potential penalty comprising a financialpenalty.
 19. The computer program product of claim 15, furthercomprising program instructions stored on the computer readable storagemedia to: determine a provisioning rate and a de-provisioning rate ofthe set of resource pools; and use the provisioning rate and thede-provisioning rate to determine the rate of consumption and thesaturation point.
 20. The computer program product of claim 15, thereallocation occurring from the on-demand based resource pool to thereservation based resource pool so the potential penalty can beminimized.